Probing the mechanism by which the retinal G protein transducin activates its biological effector PDE6.

ABSTRACT: Phototransduction in retinal rods occurs when the G protein-coupled photoreceptor rhodopsin triggers the activation of phosphodiesterase 6 (PDE6) by GTP-bound alpha subunits of the G protein transducin (Gα_T). Recently, we presented a cryo-EM structure for a complex between two GTP-bound recombinant Gα_T subunits and native PDE6, that included a bivalent antibody bound to the C-terminal ends of Gα_T and the inhibitor vardenafil occupying the active sites on the PDEα and PDEβ subunits. We proposed Gα_T-activated PDE6 by inducing a striking reorientation of the PDEγ subunits away from the catalytic sites. However, questions remained including whether in the absence of the antibody Gα_T binds to PDE6 in a similar manner as observed when the an

SUBMITTER: Aplin C 

PROVIDER: S-EPMC10838916 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature